摘要

Melbourne's Western Treatment Plant is unusual in that it employs a sequential activated sludge-lagoon (AS-lagoon) system to treat municipal wastewater. Reuse of the treated water is limited for some applications due to salt content, and membrane pre-treatment prior to reverse osmosis is under consideration. The use of microfiltration (MF) and ultrafiltration (UF) for improving the quality of water prior to reverse osmosis was investigated. The organic components of the feed water (AS-lagoon effluent), permeates and foulant layers were characterised using three-dimensional excitation-emission-matrix (EEM) spectroscopy, attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR), dissolved organic carbon (DOC) determination, size exclusion chromatography (SEC) and ultraviolet (UV) absorbance. DOC removal was 28% for UF and 2% for ME MF removed mostly non-UV absorbing molecules of AMW 40-70 kDa, whereas UF removed molecules in this size range, a high proportion of which were UV-absorbing, as well as some organic compounds in the 3-8 kDa range, some of which were UV-absorbing. The organic compounds removed by UF had hydrophobic, hydrophilic and transphilic character, and were shown to comprise humic-like matter, soluble microbial products and protein-like extracellular matter. Fulvic-like matter largely passed through the UF membrane. ATR-FTIR analysis of fouled MF and UF membranes showed that polysaccharides, polysaccharide-like compounds and proteins were the prominent components in the fouling layer.

  • 出版日期2009-1-31